Firefox 4 is also notable for what isn’t included — the venerable status bar. The status bar is an almost universal element of browsers and Mozilla decision to remove it is, well, curious.

Mozilla says that ditching the status bar gives Firefox a simpler, smaller user interface. While that’s true, it comes at the expense of something that every other browser manages to offer — URL previews in the lower left corner of the browser window.

Defenders of the change point out that all of the elements that used to be in the status bar are still in Firefox, they’re just in different places. The page load information is now displayed on each tab, and the URL preview seen when hovering links has moved to the URL bar.

It’s the later change that irks many long-time Firefox users. Part of the problem is that there simply isn’t as much room in the URL bar so URLs are truncated with ellipses, giving you less information about where a link leads.

Mozilla plans to improve the URL preview interface before the final release of Firefox 4, but that doesn’t change the fact that Firefox’s URL preview is now in a different place than every other browser on the web (Chrome and IE 9 don’t have permanent status bars, but both still show link previews in the bottom left corner of the browser window).

Luckily there’s already a Firefox add-ons that brings back the status bar. If you’re using the Firefox 4 beta and you miss the status bar, the appropriately named Status-4-Evar will restore it to its former glory.